Quick Answer
A QR code should be at least 2 by 2 centimetres for reliable scanning at close range. The bigger the scanning distance, the bigger the code needs to be, following a 10-to-1 distance-to-size rule. Always leave a clear quiet zone around it, and test one printed copy before running the full batch.
The practical minimum size for a QR code is 2 by 2 centimetres, and the right size depends on how far away people will scan it. The rule of thumb is simple: the code should be about one-tenth of the scanning distance. So a code people scan from arm's length needs to be bigger than one on a business card. Here are the exact sizes by use case, plus the resolution, quiet-zone, and testing rules that decide whether a code scans or fails.
What is the minimum size for a QR code?
The absolute technical minimum for a QR code to scan is about 1cm by 1cm. But in the real world, with varied lighting, different cameras, and shaky hands, that's too small to trust. According to Scanova, QR codes should be at least 2 centimetres by 2 centimetres to be scanned reliably by most modern devices (Scanova, scanova.io). So treat 2cm as your floor, and go bigger whenever you can.
Why the gap between the technical minimum and the practical one? A camera needs enough clear pixels to pick out the pattern. At 1cm, a slightly dim room or a cheap phone camera can push the code below the readable line. At 2cm, you've got margin for real conditions. And larger is never a problem, so when you're unsure, size up.
What is the 10-to-1 rule for QR code size?
This is the single most useful sizing rule to remember. The maximum scanning distance is roughly 10 times the size of the code, so to work out your minimum size, divide the scanning distance by 10 (QR Code Generator, qr-code-generator.com).
In practice, that means a 3cm code scans reliably from about 30cm, and a 10cm code from about 1 metre. If you expect people to scan from 2 metres away, like a code on a shop window or a poster across a room, your code needs to be at least 20cm. The 10-to-1 ratio holds up because it builds in slack for camera angle, lighting, and a bit of motion, rather than assuming a perfect lab scan.
When in doubt, make the QR code bigger. A code that's slightly too large looks confident and professional. One that's too small looks like an afterthought and frustrates people when it fails to scan.
What size should a QR code be for each use case?
Here's a quick reference for the most common print jobs, based on the 10-to-1 rule and typical scanning distances.
| Use case | Minimum size | Recommended size | Scanning distance |
|---|---|---|---|
| Business card | 2cm x 2cm | 2.5cm x 2.5cm | Up to 25cm |
| Flyer (A5) | 3cm x 3cm | 4cm x 4cm | Up to 40cm |
| Poster (A4) | 4cm x 4cm | 5cm x 5cm | Up to 50cm |
| Restaurant table card | 4cm x 4cm | 5cm x 5cm | Up to 50cm |
| Product packaging (small) | 2cm x 2cm | 3cm x 3cm | Up to 30cm |
| Window sticker / shop display | 6cm x 6cm | 8cm x 8cm | Up to 80cm |
| T-shirt print | 5cm x 5cm | 6cm x 6cm | Up to 60cm |
| Large banner / roll-up | 10cm x 10cm | 15cm x 15cm | Up to 1.5m |
| Billboard | 20cm x 20cm | 30cm x 30cm | Up to 3m |
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Why does the quiet zone matter for QR code size?
The quiet zone is the blank margin around the code, and it's not optional. The ISO/IEC 18004 standard that defines QR codes requires a quiet zone of at least 4 modules of clear space on all four sides (QRLynx, qrlynx.com). A module is one of the small squares that make up the code, so the margin should be about four squares wide all the way around (Denso Wave).
Skip it and scanners struggle to find the finder patterns, the three big squares in the corners, which is how a camera locks onto the code. Crowd the edges with text or a logo and the scan can fail even if the code itself is perfectly sized. So when you place a code, give it breathing room. That white space is doing real work, so don't crop it away to save space on a busy layout.
What resolution and file format should you use for printing?
Resolution matters as much as physical size. A code that looks crisp on screen can print blurry if the pixel count is too low, and a blurry code often won't scan.
Use SVG for all print use. SVG is a vector format with no fixed pixel size, so it scales to any dimension with perfect sharpness. Download the SVG from our free QR code generator and hand it to any printer for guaranteed clean output. If you must use PNG, download at 512px, which prints sharply up to about 4 to 5cm at 300 DPI, and never stretch a small PNG larger. As a quick DPI reference: 300 DPI is the standard for quality print, 150 DPI is fine for large formats viewed from a distance, and 72 DPI is screen-only. A 512px PNG at 300 DPI prints at roughly 4.3cm, so for anything bigger, switch to SVG.
Which QR code sizing mistakes should you avoid?
- Too small on business cards. Designers sometimes shrink the code to fit other elements. Below 2cm, it gets unreliable. Trim other elements to leave room for at least 2.5cm.
- Stretching a low-resolution PNG. Placing a 128px or 256px code at 10cm creates a blurry, unreadable result. Download at 512px minimum, or use SVG.
- Weak contrast. Light grey on white or orange on red reduces the contrast scanners rely on. Keep a strong dark-on-light contrast.
- Cropping the quiet zone. Pushing text or a border right up to the code kills the margin scanners need.
- Not testing before a bulk print. Always print one and scan it on both iPhone and Android before ordering 500 copies.
For a wider checklist beyond sizing, see our QR code best practices guide.
How do you test a QR code before printing?
- Print a single test copy at the intended final size.
- Scan from the expected distance, like arm's length for a table card or 50cm for a poster.
- Test in different lighting: bright, dim, and with a bit of glare.
- Test on both iPhone and Android if you can.
- Ask someone who's never seen the code to scan it with no guidance.
Generate your code in SVG from our free generator for sharp printing at any size. No account, no watermark. And if you're deciding between code types, our dynamic vs static QR codes guide helps you pick.
Create a Print-Ready QR Code Free →What else do people ask about QR code size?
What is the minimum size for a scannable QR code?
The technical minimum is about 1cm by 1cm, but 2cm by 2cm is the practical minimum for reliable scanning in real-world conditions. For business cards and table cards where people scan from 20 to 30cm away, 2.5cm by 2.5cm is the recommended minimum. Larger is always more reliable.
What resolution should I use to print a QR code?
For sharp print quality, use at least 300 DPI. Download the SVG version from our generator for any print size, since SVG is a vector format that scales without pixelation. If using PNG, download at 512px and do not enlarge it beyond about 5cm in print. For large format, always use SVG.
How far away can a QR code be scanned?
A practical rule is that the maximum scanning distance is roughly 10 times the QR code size. A 3cm QR code can be scanned from about 30cm, and a 10cm code from about 1 metre. For signage or billboards, size the code for your expected viewing distance.
What is the quiet zone on a QR code?
The quiet zone is the blank margin around a QR code. The ISO/IEC 18004 standard requires at least 4 modules of clear space on all four sides. Without it, scanners cannot locate the finder patterns and the scan fails, so never crop or crowd the edges of a code.
Should I use SVG or PNG for printing a QR code?
Use SVG for any print job. It is a vector format that stays perfectly sharp at any size, from a business card to a billboard. PNG is fine for on-screen use or small prints up to about 5cm if downloaded at 512px, but it blurs when enlarged.
Sources: Scanova, "Minimum QR Code Size" (scanova.io). QR Code Generator, "QR Code Minimum Size Guidelines" (qr-code-generator.com). QRLynx, "QR Code Design: Quiet Zone, Contrast and Sizing (ISO 18004)" (qrlynx.com).